Definition of prejudicing:
(n) :
(countable) An adverse judgment or opinion formed beforehand or without knowledge of the facts.
(n) :
(countable) A preconception, any preconceived opinion or feeling, whether positive or negative.
(n) :
(countable) An irrational hostile attitude, fear or hatred towards a particular group, race or religion.
(v) :
(transitive) To have a negative impact on (someone's position, chances etc.).
(v) :
(transitive) To cause prejudice in; to bias the mind of.
(n) :
(obsolete) Knowledge formed in advance; foresight, presaging.